Intermittent drive



1962 A. w. STEWART INTERMITTENT DRIVE 2 Sheets-Sheet 1 Filed Nov. 23, 1960 INVENTOR Ayred W Stewart BY W 7 fl I ATTORNEYS Oct. 9, 1962 A. w. STEWART 3,

INTERMITTENT DRIVE Filed Nov. 23, 1960 2 Sheets-Sheet 2 IN VEN TOR A lfred W Ste Wdri,

ATTORNEYS tent 3,657,215 Patented Oct. 9, 1962 3,057,215 INTERWITTENT DRIVE Alfred W. Stewart, High Falls, N.Y., assignor to Ulster- Dutchess Machine & Tool Co., Inc., Rosendale, N.Y., a corporation of New York Filed Nov. 23, 1960, Ser. No. 71,355 Claims. (Cl. 74125.5)

This invention relates to an intermittent drive. In particular, the invention is directed to an intermittent drive of the Geneva wheel type.

Intermittent drives of the Geneva type are used to produce a full or partial rotation of a driven shaft. They are ordinarily used in lightweight apparatus such as in the operation of watches and electric switches or controls. In the known types, the driving and driven shafts cannot be aligned on the same axis.

The objects of this invention are to produce a Genevatype drive suitable for apparatus having a large mass as well as for machines of low mass, especially those operating at high speed and light load, and having the driving and driven shafts in axial alignment.

In general, this and other objects of the invention are obtained by having aligned driving and driven shafts. An arm fixed to the driving shaft carries a driving pin. An arm extending outwardly of the driven shaft carries a drive wheel or gear. This wheel is adapted to slide around a stationary guide block or sector block having one or more escape notches in the surface thereof. The driving pin moves the gear which, in turn, rotates the driven shaft through the connecting arm until the engagement between the pin and gear is broken when the gear reaches an escape notch. Because of the arms and stationary guide block and aligned shafts, this structure is not only compact but very rugged and can transmit sufficient torque to drive a large mass of machinery.

The means by which the objects of the invention are obtained are described more fully with reference to th accompanying drawings, in which:

FIGURE 1 is a cross-sectional view through the intermittent drive;

FIGURE 2 is a cross-sectional view taken on the line 22 of FIGURE 1;

FIGURE 3 is a perspective view of the drive; and

FIGURE 4 is a side elevational view of a machine for both typing and punching a card with the card tray in open position and utilizing the intermittent drive of this invention.

As shown in FIGURES 1 to 3, the driving shaft is driven from motor M. An arm shown as an arm means 12, illustrated as a disc, is fixed to and extends transversely of driving shaft 10. A pin 14 is mounted in a disc adjacent the periphery thereof and extends parallel to shaft 10. The driven shaft 16 extends through machine frame 18 and a stationary guide block 20 is secured to frame 18. Shaft 16 is aligned with shaft 10. An arm 22 is fastened to driven shaft 16 transversely thereof and parallel to disc 12. A gear 24 is rotatably mounted on arm 22. Gear 24 has the form of a Maltese cross. Each tooth has its outer end 26 of concave shape and of the same curvature as the circumference of guide block 20. It is apparent that gear 24 is held against rotation by the contact of a tooth with the stationary guide block 20 until the tooth reaches the escape notch 28 formed in the circumference of block 20.

This particular intermittent drive has sufficient torque transmitting properties to drive a relatively large mass of machinery through a single cycle. When the pin 14 becomes disengaged from gear 24, the friction in the driven machinery is sufficient to cause driven shaft 16 to stop almost instantaneously, whereas the motor M can coast to a stop before pin 14 again contacts gear 24. The operation of the invention is further described with reference to a machine for the simultaneous typing and punching of a card for later use in a punch card machine.

As shown in FIGURE 4, a blank card is adapted to be placed in an open tray T, and then the tray is pushed to the right. In this position, the tray lies above a typing mechanism indicated generally at 30 and a punching mechanism indicated generally at 32. The position for the appropriate numeral is achieved by shifting one of the keys K which simultaneously sets both the typing and punching positions by means of the rack and pinion 36. Typing mechanism 30 is driven from a crank shaft, Whereas punching mechanism 32 is driven by a cam. This allows the punching mechanism 32 to function slightly in advance of and separate from the typing mechanism for the purpose of lightening the load on the power drive. Tray T, when entering fully closed position, actuates an electric switch 41 to start motor M. The motor turns the driven shaft 16 through one cycle or through about 345 to operate the typing mechanism 30 and the punching mechanism 32. At the end of the cycle, a cam is rotated to operate the lever system 48 which has the dual purpose of operating the bar 50 for returning the keys K to their starting position and for releasing tray T from the catch 52 so that the tray is withdrawn to starting position by means of the spring S.

It is apparent that the typing and punching mechanisms are of rather considerable mass and require a rather large torque to drive them. This is made possible by means of the particular drive as shown in FIGURES 1 to 3. The friction in the typing and punching mechanisms is sufficient so as to cause the driven shaft 16 to stop substantially immediately once the drive is broken from motor M. The motor then can coast to a stop through an angle of about 345. Again, the friction in the reduction gears used for the motor M is suificient to stop the motor before the pin 14 again engages gear 24.

Having now described the means by which the objects of the invention are obtained, I claim:

1. An intermittent drive comprising a rotatable driving shaft, driving arm means fixed transversely of said driving shaft and rotatable therewith, a pin joined to said driving arm means and extending parallel to said driving shaft, a rotatable driven shaft, a stationary circular guide block concentric with said driven shaft and having at least one escape notch in the circumference thereof, a driven arm secured to said driven shaft and extending transversely thereof, a gear rotatably mounted on and carried by said driven arm, said gear having one tooth engageable by said pin to turn said gear and drive said driven arm and said driven shaft, and another tooth slidably contacting the circumference of said block until said another tooth reaches said escape notch to permit rotation of said gear 3 and the breaking of the engagement of said pin with said gear to stop the driving of said driven shaft.

2. An intermittent drive as in claim 1, each tooth of said gear having its outer end curved to the curvature of said guide block. 5

3. An intermittent drive as in claim 2, said gear having four teeth.

4. An intermittent drive as in claim 3, said driving shaft being aligned with said driven shaft.

5. An intermittent drive as in claim 4, said driven 10 shaft being journalled in said guide block.

References Cited in the file of this patent UNITED STATES PATENTS Hill June 1, Morton Dec. 7, Mirfield Feb. 23,

FOREIGN PATENTS Austria Oct. 25, Great Britain Oct. 30, Great Britain Oct. 6, France Jan. 26, 

